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Gold tank plating solution -- Can it be used to brush plate?

I have loads of gold salts for a tank and I was wondering if there was any way possible to use them as brush plating solution? I was thinking if I just use less water when mixing them it should be ok. Has anyone tried this before and if so how did it work out?

David Scott
Plating shop employee - Glasgow, Scotland
2007

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2007

Hi David,

Are you referring to PGC when you said gold salts?

As far as I know, the same chemistry can be used for both gold immersion and gold brush plating, without any adjustment made. As a matter of fact, the only thing that is different is the cell design between immersion and brush.

Jen Teh
- Penang, Malaysia

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Dear David,

I think you should give it a try!

Regards

T.K. Mohan
plating process supplier - Mumbai, India
2007

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2007 -- 1st of two simultaneous responses

Hi I think I will give it a bash on some scrap metals and see what happens. I was sure it would work I was just wondering if anyone has tried it. Thanks for the info.
P.S
What's PGC?

David Scott
- Scotland

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2007 -- 2nd of two simultaneous responses

Hi David,
Since you have gold Salts, is that the gold potassium cyanide salt or conducting salts. If you have GPC you can make a new brush plating solution with higher concentrations of gold say 20 g/l, hope your existing bath is not that much high concentrated, if it is of high concentration you can make use of the same solution, if not you need to prepare a new brush plating solution.
hope the information will help you.
good luck
MUKESH

Panjala Mukesh
fashion jewelry mfgr.
Hyderabad, India

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PGC means potassium gold cyanide. Brush plating solutions can be thickened by the addition of a small amount of a thickening agent like Fumed Silica [affil links].

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2007

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First of two simultaneous responses --

A point that should not be overviewed. Remember that brush plating is performed mostly by hand very close to the operator's hands, eyes, skin and mouth. Cyanide is a poison. It is absorbed thru any tissue or via. Extreme care when handling this solution.

Guillermo Marrufo
Monterrey, NL, Mexico
2007

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Second of two simultaneous responses --

The truth be told I have no idea if they are PGC or not my supplier won't answer my e-mails. After reading a MSDS for PGC I am hoping they're not. What kind of salts are available for tank plating as all my label says is 24K gold salts?

David Scott
- Scotland
2007

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2007

I gave it a bash and it worked fine. The only problem I have now is I can't seem to brush plate well. I have been trying gold plating plastic parts. I brush plated copper, Plated back with copper wadding, cleaned the part, done the water break test, now that all went well then I tried to nickel plate. For some reason it just went dark. I got a few spots of silvery plating. I just kept going using loads of nickel then thought I'll try gold to see what happens. I got a few bits to go gold then in the mater of seconds after I stopped it all turned black. It looked like the tarnish from the copper plate.
Has any one got any idea what happened or am I doing something wrong. I've bought books and looked on the net but there is very little info on the brush plating processes. Most just tell you how to brush.
Many thanks,

David Scott
- Scotland

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Rubinstein's "Electrochemical Metallizing" is solely about brush plating, Dave.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2007

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2007

David,
It is interesting!
You have "loads of gold plating salts and it says 24 KT gold plating salt!".Sitting in Mumbai I will tell you it is not GPC or PGC -- Gold potassium Cyanide or Potassium gold Cyanide respectively and is one and the same. If it is GPC, you must have paid approx.70-72% value of Gold. If you have say,100 kgs of salt, you must have paid the value of 70-72 kgs gold as metal. (Generally 1 Kg GPC yields 630 grams of gold and balance is highly poisonous potassium cyanide). It is white sugar like crystalline salt soluble in water! You will have to pay for converting gold metal into salt. Did you pay that much?

Now coming back to your question- What kind of salts are available for gold plating-
1.Cyanide base gold plating salts
2.Acid Based gold plating salts
3.Non-cyanide base neutral baths with GPC in the bath
4.Non-cyanide base baths with non cyanide gold salts in the bath
Now to proceed further, you may have to tell us the details.
Regards,

T.K. Mohan
plating process supplier - Mumbai, India

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Hi David,

As a matter of fact, I am doing gold brush plating over here but I can't seem to quite get the predicament you are in.. Perhaps I am not familiar to the process you are talking about.. :-)

I use the same chemistry for my brush plating and gold immersion but then, just one thing to take care when doing brush plating, it gets burnt a lot easier than immersion. Thus, some sort of additives have already been incorporated to widen the operating window.

So, David, what sort of components are available in your current gold plating solution, besides your Au? On top of that, I am quite interested to know your brush plating cell design.

Thanks..

Jen Teh
- Penang, Malaysia
2007

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Thank you for all your help it is very much appreciated. I am fairly new to plating so I am a bit lost with your answers. I don't make the salts; I just bought them from a supplier it cost £131 GBP for what makes up five liters.
I think I should buy that book as I solved the tarnish on the copper problem, I can get a nice shiny copper on plastic items but for some reason I cannot get the nickel to plate on to it. I can't even get nickel to plate over gold. I use tons of the solution but it refuses to go on.

David Scott
- Scotland
2007

I just thought I'd let everyone know I found out the problem it was bad prep work. I never realised just how much you had to clean copper. Has anyone any idea how I clean a nickel plate just before gold plating as water just wasn't good enough?

Davie Scott
- Scotland
2007

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First of three simultaneous responses --

Immediately after being plated, nickel is clean and active, but it passivates quite fast upon exposure to oxygen. Once passivated it must be cleaned and activated again with a highly acidic and low efficiency nickel solution.

Guillermo Marrufo
Monterrey, NL, Mexico
2007

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Second of three simultaneous responses --

David
Only thing is that you should not waste time after nickel plate.it should be an online (continuous) process.Any GOOD WATER cleaning is good enough.
Please let me know how you use the brush.There is a technique how to use the brush!
REGARDS

T.K. Mohan
plating process supplier - Mumbai, India
2007

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Third of three simultaneous responses --

David,
It was good to hear you solved the problem with your pre-clean. As far as "cleaning" the nickel, as long as you brush plate the gold immediately after nickel and rinse, you should not have any problems. There are activators available on the market for brush plating, if the nickel becomes passive. When brush plating remember to move the wand rapidly across the part to avoid burning. Good Luck!

Mark Baker
process engineer - Syracuse, New York
2007

When I brush plate I do it in small circular motions. I do it as fast as I can. Thanks for all the info unfortunately due to illness I haven't been able to try again but I'll give it a bash and post results. On the last part I plated there are smudges under the gold on the nickel plating. It is possible I went too slow or stopped for a min. I can't find that book anywhere in the UK and I can't buy it from overseas as I don't have a credit card so I guess I will need to just keep practicing.

Davie Scott
- Scotland
2007

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Hi, Davie. It's a hard-to-find book, but it should be available somewhere in the UK -- perhaps from Metal Finishing Information Service or Amazon.com.uk. Good luck.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
March , 2009

Hi I was going over the older messages and I noticed Ted Mooney said you can thicken up the brush plating solution by adding Fumed Silica. I was told by a mate that this would makes the plating process 10 times harder. Can anyone give me any info on this as I was considering using this on my next job.

Davie Scott
- Scotland
2007

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I think you accidentally subtly misquoted what I meant to say, Davie. I am never a fan of end users formulating their own plating solutions, especially based on internet advise. I thought we were talking about possible ways to make use of a waste product from gold plating that you have on hand; sorry for any misunderstanding. Yes, it is my belief that fumed silica is a thickening agent used in some brush plating solutions but I would not dispute the advice of your mate if he has done gold brush plating successfully without it.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2007

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Dear Sir,

you can often use the present gold solution for plating. But add a thickening agent, say cobalt salt or nickel salt, with removal of organic contaminants. But the thing is you have to increase the gold conc. for brush plating solution if you are maintaining the low conc. presently.

Shafiuddin A. Mohammed
metal coating shop - Dubai, United Arab Emirates
2007

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Is copper sulphate [on eBay or Amazon]solution suitable on a plastic part sprayed with silver?
As far as I am aware copper sulphate is acid copper is that correct?

Davie Scott
- Scotland
2007

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I don't know for sure that I'm following you, Davie. You have metallized a plastic part with a two-part silvering solution and now you want to copper electroplate it? Yes, you should be able to do that.

copper sulphate is the principal component in a bright acid copper electroplating solution, but it is not the only ingredient. I'd suggest you buy a proprietary solution for this as well, but if not, then seek a formulation in the Electroplating Engineering Handbook [on AbeBooks or eBay or Amazon] or the Metal Finishing Guidebook.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
November , 2007

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March 13, 2009

Hello,
I would like to know if there is an update to this?

I too have a brush plater and I am wondering if I can buy tank plating solutions to use with my brush plater to plate car emblems?

s.j. kugle
- green bay, Wisconsin

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I can make PGC (potassium gold cyanide) and I am wondering anyone who can suggest to use PGC and make Gold brush solution, I also know that concentration of Gold brush solution is at least 4 time higher than Gold tank solution, is it possible to add small amount of Cobalt salt or cobalt chloride and make the job done? if yes, which cobalt salt is right for the job?

Kam Holland
engineer - Amsterdam-Netherlands
April 8, 2009